Fan with engagement structure

ABSTRACT

A ceiling fan includes a hub with a plurality of sockets and a plurality of blades. Each of the blades can be received in and attached to one of the sockets, which connects the blades to the hub without use of external fasteners. The structure of the blades and/or engagement structure reduce the likelihood that the fan blades will move from side-to-side in the slot or disengage from the slot.

CROSS REFERENCE TO RELATED APPLICATION

This application claims priority to U.S. Provisional Patent Application No. 62/584,660, titled “Fan with Engagement Structure” filed Nov. 10, 2017, the disclosure of which is incorporated herein by reference in its entirety for all purposes.

FIELD

This disclosure relates generally to ceiling fans and, more particularly, to structures for attaching fan blades to a ceiling fan hub.

BACKGROUND

The prior art discloses fans, such as ceiling fans, that producing a current (or flow) of air. Ceiling fans are normally used for circulating air in rooms and buildings.

A typical ceiling fan consists of a plurality of fan blades attached to a central hub. The hub and blades combined are commonly called an impeller or rotor, and the impeller can be rotated to produce a flow of air. The impeller may or may not be enclosed in a housing. The impeller may be driven by an electric motor or other power source.

Fan blades are normally fixed to the central rotating hub by conventional nut and bolt fastening mechanisms or welding. These known mechanisms for attaching fan blades to a rotating hub are time consuming when first connecting fan blades to the hub, or when replacing damaged or undesirable fan blades.

U.S. Pat. Nos. 6,059,531 and 7,008,192, the disclosure of each of which is incorporated herein by reference, disclose structures that engage a fan blade without the use of manually-applied fasteners or welds. These structures fit into and engage an opening formed (preferably in the center) in an end of a fan blade when the end of the fan blade is received in a socket of the hub. In that way the fan blade is connected to the hub. A problem with these structures is that the fan blade can move from side to side within the socket, which can cause undesirable noise and possibly lead to the blade cracking, and/or disengaging and coming out of the socket. The tolerances of the fan blade and socket are not exacting enough to alleviate this problem because of the expense of manufacturing known parts with such a fine tolerance in order to create a tight fit.

SUMMARY

Disclosed is a ceiling fan in which blades are engaged with the hub without using screws, nuts and bolts, or other conventional fasteners. Each blade has a first end that is received in a socket of the hub. The hub has a plurality of sockets, each of which is configured to receive a first end of a fan blade. A blade can be engaged in a socket and connected to the hub in several ways according to aspects of the disclosure.

In some embodiments, a first end of the fan blade has a first side and a second side. One or both of the sides can have a recess. The hub has a plurality of sockets, each of which has an engagement structure positioned at least partially therein. Each of the engagement structures has: (1) a first position in which it can engage and retain a fan blade in the socket, and (2) a second position in which it does not engage a fan blade and the first end of the fan blade can be pushed past the engagement structure or the fan blade can be removed from the socket. In one embodiment, the engagement structure is biased to the first position by any suitable biasing member, such as a spring, which can be retained in a canister and directly or indirectly attached to the engagement structure.

In one embodiment, the engagement structure includes at least a first leg, and most preferably a first leg and a second leg. When the engagement structure is in its first position, the leg(s) are inside the socket and each leg fits into a recess on a side of the fan blade to engage the fan blade in the socket. When the engagement structure is in its second position the leg(s) are moved away from the recess(es) and do not engage the fan blade. The first end of the fan blade can then be moved into the socket past the engagement structure, or the fan blade can be removed from the socket. The engagement structure may also have more than two legs and/or legs that are received in one or more openings in the fan blade body when the fan blade is engaged by the engagement structure. For example, an engagement structure may have one or two legs that engage one or two recesses, and one or more legs that are received in one or more openings in the fan blade when the fan blade is engaged in the socket.

The engagement structure can move from its first position to its second position in any suitable manner. For example, the engagement structure may move straight up and down, or move up and down at an angle, or rotate up and down around a pivot rod.

In one embodiment, the engagement structure has a front portion juxtaposed an open end of the socket. The front portion has a first height and the one or two legs have a second height greater than the first height. Each leg has a proximal surface (which is closest to the open end of the socket) and a distal surface (which is farthest from the open end of the socket). In one embodiment the proximal surface is either angled or curved so when the first end of the fan blade is inserted into the socket, it passes the front portion of the engagement structure and presses against the proximal surface(s) of the leg(s). The force applied by the first end of the fan blade pushes the legs of the engagement structure out of the way of the fan blade and moves the engagement structure to its second position. As the first end of the fan blade moves farther into the socket, the recesses on one side (or both sides) of the first end of the fan blade align with the one or two legs, and the leg(s) then move back into the first position where they are positioned at least partially in the recess(es) and engage and retain the fan blade in the socket.

The engagement structure can also, or instead, be moved from the first position to the second position manually. If moved manually, a switch is moved from a first position to a second position, which physically moves the engagement structure from its first position to its second position. As previously described, when the engagement structure is in its second position, it allows for passage of the first end of the fan blade into the socket, or removal of the fan blade from the socket. When the switch is moved, or allowed to move, back to its first position, the engagement structure moves back to its first position and can engage the fan blade as previously described.

Once engaged, the fan blade is connected to the hub and is not prone to moving to side to side when the hub and fan blades are rotated to create an air flow.

The engagement structure and/or fan blade may also include one or more surface features, such as ribs, dimples, or bumps to further create a snug fit. These surface features can be comprised of a material more flexible than metal or wood, such as a soft or semi-rigid plastic or rubber that are malleable enough to flex and help create a tight fit when used in the manner described herein. In addition, or alternatively, the engagement structure or fan blade may have a tacky surface coating, such as a urethane, epoxy, or any suitable material.

The one or more surface features and/or tacky coating may be on one or more of the (1) engagement structure, (2) bottom surface of the fan blade, (3) top surface of the fan blade, (4) side(s) of the fan blade juxtaposed the recess(es), and (5) one or more inner surfaces of the socket. As an example, the top surface, bottom surface, or both, of a fan blade may have one or more surface features and no recesses, or may still include one or more recesses and/or opening(s) to receive leg(s) of an engagement structure. If the surface features are on a surface of the engagement structure that engages a surface of the fan blade, downward or upward pressure by the biasing member that biases the engagement structure to its first position would press the surface features of the engagement structure against a surface of the fan blade.

If one or more surface features and/or a tacky coating is utilized, the engagement structure may be one as described herein or shown in U.S. Pat. Nos. 6,059,531 or 7,008,192. Or, the engagement structure may have no legs to engage the fan blade. In that case the first end of the fan blade is pushed into a socket and there is a pressure fit with the first end of the fan blade and the engagement structure.

Alternatively, there could be no engagement structure and the fan blade with surface features and/or a tacky coating would be configured to pressure fit directly into the socket.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a fan including a plurality of sockets, a plurality of fan blades, and one of the fan blades shown detached from the hub.

FIG. 2 is a fragmented side elevational view of the fan of FIG. 1 showing a fan blade detached from the hub.

FIG. 2A is a top, perspective view of a socket with the top open.

FIG. 3 is a top view of a fan blade according to aspects of the disclosure.

FIG. 4 is a top, perspective view of a fan blade and engagement structure according to aspects of the disclosure.

FIG. 5 is a bottom, perspective view of a fan blade and engagement structure according to aspects of the disclosure.

FIG. 5A is a bottom view of the engagement structure of FIGS. 4 and 5.

FIG. 6 is a front view of an engagement system according to aspects of the disclosure.

FIG. 6A is a front view of the open socket of FIG. 2A and the engagement structure of FIGS. 4, 5 and 5A.

FIG. 7 is a top perspective view of a fan blade with surface features.

FIG. 8 is a partial, cross-sectional side view of a socket including an engagement system according to aspects of the disclosure.

FIG. 9 is the socket of FIG. 8 with a fan blade being inserted therein.

FIG. 10 is the socket of FIG. 8 with a fan blade engaged by the engagement system.

FIG. 11 is a partial view of the socket of FIG. 10 taken along line A-A.

FIG. 12 is an alternate partial, cross-sectional side view of a socket including an engagement system according to aspects of the disclosure.

FIG. 13 is the socket of FIG. 12 with a fan blade being inserted therein.

FIG. 14 is the socket of FIG. 12 with a fan blade engaged by the engagement system.

FIG. 14A is a top, perspective view of a switch and engagement structure according to aspects of the disclosure.

FIG. 14B is a front, perspective view of a switch and engagement structure according to aspects of the disclosure.

FIG. 14C is a front, perspective view of a switch and engagement structure according to aspects of the disclosure.

FIG. 15 is a top view of an alternate fan blade that has one recess.

FIG. 16 is an end view of an alternate engagement structure that has one leg.

FIG. 17 is a top view of an alternate fan blade that includes surface features.

FIG. 18 is a top view of an alternate fan blade that includes surface features.

FIG. 19 is a perspective, top view of an alternate embodiment of the disclosure with a biasing member attached to a surface of an engagement structure.

FIG. 19A is a bottom view of the engagement structure shown in FIG. 19.

FIG. 19B is a front view of the engagement structure shown in FIG. 19 with a biasing member.

FIG. 19C is a top view of the socket of FIG. 19.

FIG. 19D is a top view of the fan blade of FIG. 19 showing legs 40A, 40B, and 40F engaged with structures of the fan blade.

FIG. 19E is an alternate engagement member having an inner surface with surface features.

FIG. 20 is a side, cross-sectional view of the embodiment of FIG. 19 with no control slot or fan opening, or central leg.

FIG. 21 is a side, cross-sectional view of the embodiment of FIG. 19 with a control slot and fan opening, and a central leg.

FIG. 22 is a cross-sectional side view of a fan blade being inserted into a socket.

FIG. 23 is a cross-sectional side view of a fan blade being inserted into a socket.

FIG. 24 is a cross-sectional side view of a fan blade being inserted into a socket wherein the socket is positioned in a hub.

FIG. 25 is a cross-sectional side view of the fan of FIG. 24 engaged in a socket in a hub.

FIG. 26 is a cross-sectional side view of the fan of FIG. 25 being removed from the socket.

FIG. 27 is a top, partial view of an engagement structure attached to a pivot rod having a spring in accordance with aspects of the disclosure.

FIG. 28 is a top, partial view of an engagement structure attached to a pivot rod having a spring in accordance with aspects of the disclosure.

FIG. 28A is a top view of a switch attached to a pivot rod.

FIG. 2813 is a top view of an engagement structure attached to a pivot rod.

FIG. 28C is a top, expanded view of a pivot rod with the switch and engagement structure of FIGS. 28A and 28B attached thereto.

FIG. 29 is a side, cross-sectional view of a socket with a pivot rod positioned in the upper part of the socket.

FIG. 30 is a side, cross-sectional view of the socket of FIG. 29 with a switch and engagement structure attached to the pivot rod.

FIG. 31 is a side, cross-sectional view of the structure of FIG. 30 showing the switch being pulled to its second position in order to move the engagement structure to its second position.

FIG. 32 is a side, perspective view of the engagement structure of FIGS. 30-31 showing the switch pulled partially towards its second position.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

The disclosed embodiments include a fan blade and engagement structure configured to help alleviate side to side movement of a fan blade in the socket of a ceiling fan. The structures disclosed herein, and similar structures that will be understood by reviewing this disclosure, may be utilized for this purpose.

Engagement Structure to Engage a Recess on At Least One Side of a Fan Blade

Turning now to the drawings, where the purpose is to describe preferred embodiments and not to limit the scope of the claims, FIG. 1 shows a perspective view of a fan 10 having an impeller 11 including a plurality of fan blades 12 for displacing air, wherein each fan blade can be engaged to hub 13 by an engagement structure 15. In this example, fan 10 is a ceiling fan with impeller 11 partially carried in a decorative housing 9 and suspended for rotation from, for instance, a ceiling (not shown). Hub 13, and hence fan 10 may be rotated by an electric motor or other suitable device. In the embodiment shown, fan 10 has four sockets 31 and four fan blades 12, wherein one of fan blades 12 is received in one of sockets 31. Any number of sockets and fan blades, however, may be utilized.

Fan blade 12 has a body portion 20 that includes sub-body portion 20A, a first end 21, a first side 22 having a fan stop 22A, a second side 24 having a fan stop 24A, a top surface 23, and a bottom surface 25. Fan blade 12 can be comprised of any suitable material(s). Sub-body portion 20A can be of any suitable configuration to be engaged in a socket 31 of a hub 13. As shown sub-body portion 20A has a first, angled side 27 and a second, angled side 29. Each side 27 and 29 terminate at body portion 20 and at corners 21A and 2113, respectively. The open spaces 27A and 29A are referred to herein as recesses and are the spaces defined by reduced area of sub-body 20A as compared to the area of body 20. Recesses 27A and 29A are each configured to receive a leg 40A, 40B of engagement structure 15, as explained in more detail below.

As shown, first end 21 of fan blade 12 has a curved shape and defines rounded corners 21A and 21B. The curved shape preferably approximately matches a curvature of hub 13 that fan blade 12 can be inserted into a socket 31 and not be impeded by striking hub 13 before being engaged with engagement structure 15. Any suitable shape of first end 21 or fan blade 12, however, may be utilized. In the embodiment shown, first end 21 does not touch hub 13 when engaged with engagement structure 15.

Hub 13 includes, preferably at spaced radial intervals, a plurality of sockets 31 and an engagement structure 15 for each socket 31. Each socket 31 extends into hub 13 and has an open end 31A, a second end 31B, and one or more socket stops 31C. As shown in this embodiment, there are two socket stops 31C positioned in each socket 31.

Referring to FIG. 4, each engagement structure 15 is positioned at least partially in a socket 31. The engagement structure 15 could be positioned at either the top or bottom of the socket 31, although it is shown positioned at the top.

Engagement structure 15 as shown has a front 15A, a back 15B, a body portion 15C, a first side 16, a second side 18, an outer surface 17, an inner surface 19, a first leg 40A, and a second leg 40B. Engagement structure 15 can be comprised of any suitable material(s).

As shown in FIG. 6, body portion 15C has a height H1 and each of legs 40A and 40B has a height H2 that is greater than the thickness H1. When engagement structure 15 is in its first positon in socket 31, it is configured such that the first end 21 of the fan blade can be inserted into socket 31 without being impeded by body portion 15C, and height H1 is selected accordingly. Height H2 is selected so that legs 40A and 40B extend far enough into socket 31 when engagement member 15 is in its first position to engage one or more recesses 27A and 29A. Accordingly, first end 21 of fan 12 will push against legs 40A and 40B while end 21 is being inserted into a socket 31.

First end 21 can be pushed into socket 31 past legs 40A and 40B by: (1) forming legs 40A and 40B so they move out of the path of fan 12 when it is pressed against by first end 21, or (2) using a switch (or control) to move legs 40A and 40B out of the way to allow end 21 to pass legs 40A, 40B. As shown in FIGS. 8-14, legs 40A and 40B each has a proximal side 40C (nearest the opening 31A to socket 31) and a distal side 40D (farthest the opening 31A to socket 31). Each proximal side 40C can be angled or curved as shown in FIGS. 8-14. If the proximal side 40C of the leg(s) 40A, 40B is configured to move out of the path of first end 21, when the first end 21 of fan blade is pressed against proximal side 40C of legs 40A, 40B, the leg(s) are moved out of the path of fan blade 12 allowing first end 21 to move past legs 40A, 40B and farther into the socket 31.

As shown in FIGS. 12-14, a switch 1000 (which is optional) can be used to manually move the engagement structure 15 and legs 40A and 40B. In this embodiment, switch 1000 and engagement structure 15 are directly or indirectly connected. Switch 1000 has a first position in which engagement structure 15 is in its first position, and switch 1000 has a second position in which engagement structure 15 is in its second position. Moving switch 1000 to its first position moves engagement structure 15 to its first position, and moving switch 1000 to its second position moves engagement structure to its second position.

As shown in FIGS. 14A and 14B, switch 1000 is formed as a clasp that can be manually pushed and/or pulled to its first position and second position. In this embodiment, pivot rod 1050 is positioned at the open end 31A of socket 31. Both switch 1000 and engagement member 15 as shown are connected to a pivot rod 1050 and each move radially around pivot rod 1050 when moved from the first position to the second position, or from the second position to the first position.

In alternate embodiment shown in FIGS. 14C, pivot rod 1050 is positioned at or near the closed end 31B of socket 31. Switch 1000 is positioned so it is connected to pivot rod 1050, and in this position when switch 1000 is moved to its second position it moves engagement structure 15 to its second position.

The embodiments shown have a pivot rod near the top of socket 31, but the pivot rod could be instead near the bottom of socket 31 and switch 1000 could be outside of the bottom inner surface of socket 31.

A biasing member 1080, such as spring 1090, can be positioned directly or indirectly between the engagement member 15 and any suitable structure, such as part of socket 31 or hub 13, to bias engagement member 15 to its first position. As shown in FIGS. 8-14, one or more biasing structures, such as spring 1090, having an end 51 captured against hub 13 in a recess 52, and another end 53 positioned against a top or bottom surface of engagement structure 15, may be utilized. Instead of compression spring 1090, an elastomeric structure or other device may be used to bias engagement structure 15 to its first position,

As shown in FIGS. 8-14, the biasing member 1080 is a spring 1090 that is at least partially retained in a canister 1095. Spring 1090 applies downward pressure on engagement structure 15 to bias it towards it first position. Alternatively, the biasing member 1080 may be juxtaposed to the bottom, instead of the top of socket 31. In that case, engagement structure 15 would have a second position wherein it is at least partially outside socket 31 at the bottom of socket 31.

To attach a fan blade 12 to hub 13, a selected one of fan blades 12 may be held, such as by one or more human hands, to position it at an opening 31A of one of the sockets 31. Proximal end 21 of the fan blade 12 is then inserted into the socket 31, as generally illustrated in FIGS. 8-10 and 12-14. Proximal end 21 may then be moved into socket 31 in the direction generally indicated by the arrowed line B in FIGS. 8-9 and 12-13. As proximal end 21 is moved into socket 31, first end 21 abuts against angled or curved proximal sides 40C, which pushes legs 40A, 40B out of the path of fan blade 12 and (as shown in this embodiment) to rotate upwards (although the legs could move radially downwards, and need not move radially around pivot rod 1050), and overcome the bias of compression spring 1090 (if used) to move engagement structure 15 from its first position to its second position, which is generally away from socket 31 as shown in FIGS. 9 and 13.

As proximal end 21 is pressed farther into socket 31, recesses 27A and 29A align with legs 40A, 40B such that the legs move back into their first position and engage fan blade 12. In the first position, the legs 40A, 40B substantially engage against angled sides 27 and 29, which inhibits fan blade 12 from releasing outwardly from socket 31 and providing for the detachable engagement of fan blade 12 with socket 31 and, hence, hub 13.

In the embodiment shown, one or more socket stops 31A and 31B are preferably positioned in socket 31. When fan blade 12 is pressed into socket 31 indentations fan stops 22A and 24A strike socket stops 31A and 31B, which prevents fan blade 12 from advancing farther into socket 31. Fan stops and socket stops need not be used, in which case a fan blade is inserted into a socket 31 until engaged by engagement member 15.

To release fan blade 12 from socket 31, the engagement structure 15 is moved to its second position to release the first end 21 of fan blade 12. Referring to FIGS. 8-10 and 12-14, hub 13 may be provided with a channel or way 60 extending inwardly therethrough into each socket 31 in substantial opposition to engagement structure 15 at a recess 27A or 29A of fan blade 12. To move engagement structure 15 from its first position to its second position, an implement 61, such as a pen, screwdriver, or awl, may be inserted into way 60, which moves through a recess 27A or 29A, to press against engagement structure 15 (and overcome the bias of biasing member 1080, if used) to move engagement structure 15 from its first position to the second position. Implement 61 may then be removed from way 60 and fan blade 12 pulled out of socket 31.

Alternatively, engagement structure 15 is moved to the second position to release fan blade 12 by moving switch 1000 to its second position.

Alternatively, engagement structure 15 is moved to its second position by pulling on a release structure attached to biasing member 1080, as disclosed in U.S. Pat. No. 7,008,192.

In an alternate embodiment, fan blade 12 need only have one recess. In that case, the engagement structure could only have a single leg, such as either leg 40A or leg 40B, to engage the one recess. Or, the engagement structure could still have two legs, such as 40A and 40B, each of which move independently of the other in order for one of the legs to engage the one recess.

In another alternate embodiment, fan blade 12 would have two recesses, such as recesses 27A and 29A, and engagement structure 15 would have only one leg, such as 40A or 40B, that would engage one of the two recesses.

In another embodiment, the fan blade has one or more recesses and one or more openings through sub-body 20A. In that case an engagement member would include structures to engage at least one of the recesses and at least one of the openings through in sub-body 20A. Types of openings through a fan body that are configured to receive structures to retain a fan blade are disclosed in U.S. Pat. Nos. 6,059,531 and 7,008,197.

Other Embodiments

An engagement member could be in direct contact with a biasing member, such as a spring, as shown in U.S. Pat. No. 6,059,531 or U.S. Pat. No. 7,008,192. In this respect, if an engagement member according to the disclosure has more than one leg (for example, it has legs 40A and 40B), each individual leg could have a separate biasing member attached to it and there would then be no need for any other part of the engagement structure. For example, each individual leg could be connected to an independent biasing member of the type shown in either U.S. Pat. No. 6,059,531 or U.S. Pat. No. 7,008,192. Or, the engagement structure may have a body, as shown for engagement structures 15 and 15″ that connects a plurality of legs, in which case only one biasing member need be used to bias the engagement structure with its legs) to the first position.

Turning to FIGS. 19-26, another embodiment of the disclosure is shown. In this embodiment, the biasing member 1080 includes a canister 43A that includes a spring 1090 retained therein. Second end 1092 of spring 1090 is positioned against a surface of flange 42A, while a center tube 48A is positioned in the center of spring 1090A. Canister 43A retains spring 1090 and flange 42A and has an outer flange 44A. Fasteners 52A connect canister 43A to the top of socket body 32 as shown. In this embodiment, flange 42A fits through opening 32A and presses against an engagement member, such as member 15. If engagement member 15 is connected to a pivot rod, such as pivot rod 1050, the engagement member pivots between its first position and its second position.

As shown, a handle 58A with a loop 60A is connected to a catch 50A in order to manually pull spring 1090 upwards (as shown) or downwards to its second, compressed position. Flange 42A may be connected to the engagement member so that it moves the engagement member to its second position when spring 1090 is pulled to its second position. Alternatively, as previously described, there may be an opening in socket 31 that permits a tool to be inserted to push the engagement member to its second position, wherein spring 1090 would be compressed. In that case flange 42A does not need to be connected to the engagement member.

FIG. 19A is a bottom view of the engagement structure 15″ shown in FIG. 19. Engagement structure 15″ has legs 40A, 40B, and 40F that extend from body portion 15C′. Struts 17′ connect to pivot rod 1050. Alternatively, pivot rod 1050 may include a spring that biases engagement member 15″ to its first position, or engagement member 15″ may not be connected to a pivot rod and move straight up and down as biasing member 1080 moves up and down.

FIG. 19B is a front view of the engagement structure shown in FIG. 19 with part of biasing member 1080 and showing how flange 42A can be connected to engagement structure 15″ by fasteners 52A. FIG. 19C is a top view of the socket of FIG. 19 and shows opening 33 in the top of socket body 32.

FIG. 19D is a top view of the fan blade 12′ of FIG. 19 showing legs 40A, 40B, and 40F engaged, respectively, with recesses 27A, 29A, and opening 62A of fan blade 12′.

FIG. 19E is an alternate engagement member 15S having an inner surface the surface facing the inside of socket 31′) with surface features 2000.

FIG. 20 shows flange 42A and engagement structure 15, wherein the flange 42A is connected to engagement structure 15 by fasteners 52A, which as shown are screws, although any suitable fastener could be used. Optionally, flange 42A (or other suitable structure) need not be secured to the engagement structure, as long as it biases the engagement structure to its first position. Engagement structure 15′ has two openings 15F configured to receive and retain fasteners 52A.

FIG. 21 shows an alternate engagement structure 15″ that is the same as engagement structure 15′ of FIG. 20 except that it includes an optional central leg 40F that fits through optional opening 31F and is received in optional opening 62A in the body of fan blade 12′. Fan blade 12′ is structurally the same as fan blade 12 except that it includes opening 62A. As used herein, the term central refers to a leg that is configured to be received in an opening, such as opening 62A, in the fan blade body. Such an opening is between recesses 27A and 29A if recesses 27A and/or 29A are utilized with fan blade 12′. Opening 62A can be located at any suitable location in the fan body, and fan blade 12′ could include more than one opening 62A. Such an opening need not be at the center position of fan blade 12.

FIG. 22 shows the structure of FIGS. 19 and 21 with biasing member 1080 and engagement structure 15″ both in their first position. Fan blade 12′, with optional opening 62A, is being pressed into socket 31. FIG. 23 shows how blade 12′ pushes biasing member 1080 and engagement structure 15″ to their second position so that first end 21 of fan blade 12′ can pass farther into socket 31. Then recesses 27′, 29′, and opening 62A align, respectively, with legs 40A, 40B and 40F. Then the biasing force of biasing member 1080, which includes spring 1090, pushes engagement structure 15″ back to its first position in which legs 40A, 40B respectively engage recesses 27A and 29A, and leg 40F is received in and engages opening 62A. Alternatively, there need not be an opening 62A and leg 40F, and/or there may be only one leg 40A, 40B, and/or one recess 27A, 29A. Any suitable engagement structure and fan blade may be utilized.

FIGS. 24-26 show a hub 13 with a socket 31 and fan blade 12′ according to aspects of the disclosure. The structures in FIGS. 24-26 are the same as those described for FIGS. 19 and 21-23. The structure of FIG. 20 could also be utilized. FIG. 24 shows a fan blade 12 being pressed into a socket 31. FIG. 25 shows fan blade 12 engaged by engagement structure 15″ with leg 40F positioned in opening 62A (legs 40A, 40B and recesses 27A, 29A are not shown). FIG. 26 shows biasing member 1080 (and spring 1090) pulled via handle 68A to its second position, which in this embodiment pulls engagement member 15″ (with legs 40A, 40B, and 40F) to its second position. That allows the removal of fan blade 12 from socket 31. Alternatively, there need not be an opening 62A and leg 40F, and/or there may be only one leg 40A, 40B, and/or one recess 27A, 29A.

FIGS. 27-28 show a top view of an embodiment having engagement structure 15 having first end 15A attached to pivot rod 1050. Any suitable engagement structure may be used, however. Pivot rod 1050 has a first end 1051 received in one side of socket body 32 and a second end 1052 received in the opposite side of socket body 32. A spring 1090A is positioned on pivot rod 1050 between the two sides of socket body 32 and biases engagement structure 15 to its first position. Any suitable engagement structure, however, may be utilized. In this embodiment, a surface (either top or bottom, and preferably top) of socket body 32 is at least partially open to allow the engagement structure to move through the opening to its second position.

FIGS. 28A and 28B show, respectively a switch 1000 positioned on a pivot rod 1050 having a spring 1090A, and an engagement structure 15 positioned on pivot rod 1050 with spring 1090. In this embodiment, switch 1000 is connected to rod 1050 outside of the connections of engagement structure 15 to rod 1050.

FIG. 32 is an expanded view showing switch 1000 and engagement member 15 each attached to pivot rod 1050.

FIG. 29 shows the socket 31 of FIGS. 27-28 with pivot rod 1050. FIG. 30 shows the socket of FIG. 29 with switch 1000 of FIG. 28A and the engagement member 15 of FIG. 28B attached to rod 1050, wherein switch 1000 and engagement member 15 are each in their first position.

FIG. 31 shows the embodiment of FIG. 30, wherein the switch 1000 is moved to its second position, which moves engagement member 15 to its second position. FIG. 33 shows switch 1000 and engagement structure 15 attached to pivot rod 1050 with switch 1000 beginning to move towards its second position and engagement structure 15 still in its first position.

Alternatively, one or more legs according to aspects of the invention may be independent of one another and have a separate biasing member associated with it. For example, the structure shown in U.S. Pat. No. 6,059,531 or 7,008,192 may be used for multiple legs to be biased to their first position. Or, such structure may be associated with an engagement member that includes multiple legs, such as engagement structures 15 and 15″.

Movement of an Engagement Structure

An engagement structure according to this disclosure can move downward (as shown in the Figures) or upwards into its first position from its second position to engage a fan blade. It may move upwards (as shown in the Figures) or downwards into its second position from its first position to engage a fan blade. It may move straight up and down from its first position to its second position and back, or move upwards and downwards at an angle, or move upwards and downwards along a curve, such as along a circular curve around a pivot rod. An engagement structure could also move side to side to engage one or more recesses, such as one or both of recesses 27A, 29A.

Surface Features With or Without an Engagement Structure

The engagement structure, such as engagement structure 15′ or 15″, 15 and/or fan blade 12 or 12′, and/or one or more inner surfaces of socket 31 may also include one or more surface features 2000, such as ribs, dimples, or bumps to further create a snug fit of fan blade 12 in a socket 31. The surface features could be formed in a surface material of a surface, which may be a flexible or semi-flexible plastic or rubber. The surface features may have a durometer of between 30-60 Shore A. In addition, or alternatively, an engagement structure, fan blade and/or inner surfaces of the socket may have a tacky surface coating, such as a urethane or rubber. The tackiness of a coating may be such that a peak force to pull a structure having a tacky surface from one that does not have a tacky surface is from minus 1.0 to minus 4.0 Newtons as measured in accordance with the test method disclosed in Assessing Tackiness and Adhesion Using a Pull Away Test on a Rotational Rheometer (2015) Malvern Instruments Worldwide.

The one or more surface features and/or tacky coating may be on one or more of the: (1) an inner surface 17 of the engagement structure 15, (2) bottom surface 25 of the fan blade 12, (3) top surface 23 of the fan blade 12, and (4) one or more inner surfaces 31C, 31D of the socket 31. As an example, the top surface 23, bottom surface 25, or both, of a fan blade may have one or more surface features and no recesses such as recesses 27A, 29A, or the fan blade may still include one or more recesses. If one or more surface features and/or a tacky coating is utilized, the engagement structure may be different than the ones described above, such as the one as shown in U.S. Pat. Nos. 6,059,531 or 7,008,192. Or, the engagement structure may have an inner surface 17 with one or more surface features. In that case the first end 21 of the fan blade 12 is pushed into a socket 31 and there is a pressure fit with the first end 21 of the fan blade 12 and the inner surface 17 engagement structure 15. Downward or upward pressure by the inner surface 17 engagement structure would press the surface features of the engagement structure against a surface (23 or 25) of the fan blade.

Alternatively, if the fan blade and/or socket has surface features and/or a tacky surface, there could be no engagement structure and the first end of the fan blade would be configured to pressure fit directly into the socket.

Alternatively, the surface features could be on a surface of the engagement structure that engages a surface of the fan blade, in which case a biasing member exerting force on the engagement member to force it towards its first position would press the surface features and/or tacky surface of engagement structure against a surface of the fan blade.

Some exemplary non-limiting embodiments of the disclosure are set forth below:

EXAMPLE 1

A ceiling fan comprising a hub with a plurality of sockets, wherein each socket has an open end and is configured to receive a first end of a fan blade, wherein the ceiling fan further comprises:

an engagement structure positioned at least partially in each socket, the engagement structure having a first position in which it does not engage the first end of the fan blade and a second position in which it engages the first end of the fan blade; and

the first end of the fan blade has a first side and a second side, wherein the first side has a first recess and the second side has a second recess and the engagement structure comprises a first leg that engages the first recess when the engagement structure is in its first position, and a second leg that engages the second recess when the engagement structure is in its first position.

EXAMPLE 2

The ceiling fan of example 1, wherein the first end of the fan further comprises one or more surface features.

EXAMPLE 3

The ceiling fan of examples 2 or 3, wherein the engagement structure further comprises one or more surface features.

EXAMPLE 4

The ceiling fan of example 2, wherein the engagement structure comprises one or more surface features that engage the one or more surface features on the first end of the fan blade when the engagement structure is in its first position.

EXAMPLE 5

The ceiling fan of any of examples 1-4, wherein the first end of the fan blade further comprises a tacky surface.

EXAMPLE 6

The ceiling fan of any of examples 1-5, wherein the engagement structure further comprises a tacky surface that is configured to be pressed against the first end of the fan blade when the engagement structure is in its first position.

EXAMPLE 7

The ceiling fan of example 5, wherein the engagement structure comprises a tacky surface that is configured to be pressed against the first end of the fan blade when the engagement structure is in its first position.

EXAMPLE 8

The ceiling fan of any of examples 1-7, wherein the fan blade has a top surface and a bottom surface and a tacky coating on one or both of the top surface and the bottom surface.

EXAMPLE 9

The ceiling fan of any of examples 1-8, wherein the engagement structure further comprises a body portion with height H1 and the first leg and the second leg each have a height 1-12, wherein 1-12 is greater than H1.

EXAMPLE 10

The ceiling fan of example 9, wherein the socket has an interior height and the first end of the fan has a thickness that is less than the combined interior height of the socket and

EXAMPLE 11

The ceiling fan of any of examples 1-10, wherein the first leg and second leg each have a side that is curved or angled.

EXAMPLE 12

The ceiling fan of any of examples 1-11 that includes a plurality of sockets and a plurality of fan blades, wherein one of the plurality of fan blades is received in one of the plurality of sockets.

EXAMPLE 13

The ceiling fan of example 12 that comprises four sockets one fan blade in each socket.

EXAMPLE 14

The ceiling fan of any of examples 1-13, wherein the engagement structure is biased to the first position.

EXAMPLE 15

The ceiling fan of example 14, wherein the engagement structure is biased to the first position by a spring.

EXAMPLE 16

The ceiling fan of any of examples 1-15, wherein each leg has a proximal side configured to move the engagement structure into the second position in response to pressure from the first end of the fan against the proximal side.

EXAMPLE 17

The ceiling fan of any of examples 1-16, wherein the engagement structure can be moved between its first position and its second position by a manual switch.

EXAMPLE 18

The ceiling fan of example 17, wherein the switch is directly or indirectly connected to the engagement structure.

EXAMPLE 19

The ceiling fan of any of examples 1-18 that further incudes a pivot rod around which the engagement structure pivots from its first position to its second position and its second position to its first position.

EXAMPLE 20

The ceiling fan of example 17 or 18 that further incudes a pivot rod around which the engagement structure and the manual switch pivot.

EXAMPLE 21

A ceiling fan having a hub with a plurality of sockets, wherein each socket has an open end and is configured to receive a first end of a fan blade, wherein the first end of the fan blade has a top surface and a bottom surface, and one or more surface features on one or both of the top surface and the bottom surface, wherein the surface features help create a pressure fit of the fan blade in the socket.

EXAMPLE 22

The ceiling fan of example 21, wherein the top surface of the fan blade comprises one or more surface features.

EXAMPLE 23

The ceiling fan of example 21 or 22, wherein the bottom surface of the fan blade comprises one or more surface features.

EXAMPLE 24

The ceiling fan of example 21 or 22, wherein the top surface and bottom surface of the fan blade comprises one or more surface features.

EXAMPLE 25

The ceiling fan of any of examples 21-24, wherein the engagement structure has an inner surface including one or more surface features.

EXAMPLE 26

The ceiling fan of any of examples 21-25, wherein the one or more surface features are raised ribs on the top surface of the fan blade.

EXAMPLE 27

The ceiling fan of example 26, wherein the raised ribs have a height from 1/32″ to ⅛″.

EXAMPLE 28

The ceiling fan of any of examples 21-27, wherein the socket has a bottom inner surface that includes one or more surface features.

EXAMPLE 29

The ceiling fan of any of examples 21-28 that further comprises an engagement structure positioned at least partially in the socket, the engagement structure having a first position in which it does not engage the first end of the fan blade and a second position in which it engages the first end of the fan blade.

EXAMPLE 30

A ceiling fan comprising a hub with a plurality of sockets, wherein each socket has an opening and is configured to receive a first end of a fan blade, wherein the first end of the fan blade has a top surface and a bottom surface and a tacky coating on one or both of the top surface and the bottom surface, wherein the tacky surface is configured to assist in retaining the fan blade in the socket.

EXAMPLE 31

The ceiling fan of example 30, wherein the top surface of the fan blade comprises a tacky surface.

EXAMPLE 32

The ceiling fan of example 30, wherein the bottom surface of the fan blade comprises a tacky surface.

EXAMPLE 33

The ceiling fan of example 30, wherein the top surface and bottom surface of the fan blade each comprises a tacky surface.

EXAMPLE 34

The ceiling fan of any of examples 30-33, wherein the engagement structure has an inner surface that comprises a tacky surface.

EXAMPLE 35

The ceiling fan of any of examples 30-34, wherein the tacky surface comprises urethane.

EXAMPLE 36

The ceiling fan of example 35, wherein the urethane has a durometer of 40-60 Shore A.

EXAMPLE 37

The ceiling fan of any of examples 30-36, wherein the socket has a bottom inner surface that includes a tacky surface.

EXAMPLE 38

The ceiling fan of any of examples 30-37 that further comprises an engagement structure positioned at least partially in the socket, the engagement structure having a first position in which it does not engage the first end of the fan blade and a second position in which the engagement structure engages the first end of the fan blade.

EXAMPLE 39

A ceiling fan comprising a hub with a plurality of sockets, wherein each socket has an opening and is configured to receive a first end of a fan blade, wherein the ceiling fan further comprises:

an engagement structure positioned at least partially in each socket, the engagement structure having a first position in which it does not engage the first end of the fan blade and a second position in which the engagement structure engages the first end of the fan blade; and

the first end of the fan blade has a first side and a second side, wherein the first side has a first recess and the second side has a second recess and the engagement structure has at least one first leg that engages either the first recess or the second when the engagement structure is in its first position.

EXAMPLE 40

The ceiling fan of example 39, wherein the first end of the fan further comprises one or more surface features.

EXAMPLE 41

The ceiling fan of example 39 or 40, wherein the engagement structure further comprises one or more surface features that engage the first end of the fan.

EXAMPLE 42

The ceiling fan of example 41, wherein the engagement structure further comprises one or more surface features that engage the one or more surface features on the first end of the fan blade when the engagement structure is in its first position.

EXAMPLE 43

The ceiling fan of any of examples 39-42, wherein the first end of the fan blade further comprises a tacky surface.

EXAMPLE 44

The ceiling fan of any of examples 39-43, wherein the engagement structure further comprises a tacky surface that is configured to be pressed against the first end of the fan blade when the engagement structure is in its first position.

EXAMPLE 45

The ceiling fan of any of examples 39-44, wherein the fan blade has a top surface and a bottom surface and a tacky coating on one or both of the top surface and the bottom surface.

EXAMPLE 46

The ceiling fan of any of examples 39-45, wherein the engagement structure has a front portion with height HI and the at least one leg has a height H2, wherein H2 is greater than H1.

EXAMPLE 47

The ceiling fan of example 46, wherein the socket has an interior height and the first end of the fan has a thickness that is less than the combined interior height of the socket and H1.

EXAMPLE 48

The ceiling fan of any of examples 39-47, wherein the at least one leg has a proximal side that is curved or angled.

EXAMPLE 49

The ceiling fan of any of examples 39-48 that includes a plurality of sockets and a plurality of fan blades, wherein one of the plurality of fan blades is received in one of the plurality of sockets.

EXAMPLE 50

The ceiling fan of example 49 that comprises four sockets one fan blade in each socket.

EXAMPLE 51

The ceiling fan of any of examples 39-50, wherein the engagement structure is biased to its first position.

EXAMPLE 52

The ceiling fan of example 51, wherein the engagement structure is biased to its first position by a spring.

EXAMPLE 53

The ceiling fan of any of examples 39-52, wherein the one or more legs each has a proximal side configured to engage the end of the fan blade and move the engagement structure into the second position in response to pressure from the first end of the fan blade.

EXAMPLE 54

The ceiling fan of any of examples 39-53, wherein the engagement structure can be moved between its first position and its second position by a manual switch.

EXAMPLE 55

The ceiling fan of example 54, wherein the switch is directly or indirectly connected to the engagement structure.

EXAMPLE 56

The ceiling fan of any of examples 39-55 that further incudes a pivot rod around which the engagement structure pivots.

EXAMPLE 57

The ceiling fan of example 54 or 55 that further incudes a pivot rod around which the engagement structure and the manual switch pivot.

EXAMPLE 58

A ceiling fan blade comprising: a first end and a second end, wherein the first end has a first side and a second side, and a first recess formed in either the first side or the second side, and the engagement structure comprises one leg that engages either the first recess or the second recess when the engagement structure is in its first position.

EXAMPLE 59

The ceiling fan blade of example 58 that has a first recess formed in the first side and a second recess formed in the second side.

EXAMPLE 60

The ceiling fan blade of any of examples 58-59 that further includes one or more openings between the first side and the second side, wherein the opening is configured to receive a central leg of the engagement structure, and the engagement structure further comprises a central leg.

EXAMPLE 61

The ceiling fan blade of any of examples 58-60 that further has a top side and a bottom side and that comprises surface features on either the top side, the bottom side, or the top side and the bottom side.

EXAMPLE 62

The ceiling fan blade of any of examples 57-60 that further includes a top surface and a bottom surface and that comprises a tacky coating on either the top surface, the bottom surface, or the top surface and the bottom surface.

EXAMPLE 63

The ceiling fan blade of example 61 or 62, wherein the surface features are plastic or rubber.

EXAMPLE 64

The ceiling fan blade of any of examples 61-63, wherein the surface features have a durometer of 40-60 Shore A.

EXAMPLE 65

The ceiling fan blade of any of examples 62-64, wherein the tacky coating has a tackiness such that a peak pull force to pull the surface having the tacky coating from the opposing fan surface that does not have a tacky surface is minus 1.0 Newtons to minus 4.0 Newtons.

EXAMPLE 66

The ceiling fan blade of any of examples, wherein the fan blade has a top side and a bottom side, and that comprises surface features on either the top side, the bottom side, or the top side and the bottom side.

EXAMPLE 67

The ceiling fan blade of any of examples 1-57 or 66, wherein the fan blade has a top side and a bottom side, and that comprises a tacky coating on either the top surface, the bottom surface, or the top surface and the bottom surface.

EXAMPLE 68

The ceiling fan blade of example 66 or 67, wherein the surface features are plastic or rubber.

EXAMPLE 69

The ceiling fan blade of any of examples 66-68, wherein the surface features have a durometer of 40-60 Shore A.

EXAMPLE 70

The ceiling fan blade of any of examples 67-69, wherein the tacky coating has a tackiness such that a peak pull force to pull the surface having the tacky coating from the opposing fan surface that does not have a tacky surface is minus 1.0 Newtons to minus 4.0 Newtons.

EXAMPLE 71

The ceiling fan blade of any of examples 1-57 or 66-70 that further includes one or more socket stops in the socket and one or more fan blade stops on the fan blade.

EXAMPLE 72

The ceiling fan blade of example 71 that includes two socket stops and two fan blade stops.

EXAMPLE 73

The ceiling fan blade of any of examples 1-57 or 66-72 that further includes one or more openings in the fan blade, wherein each of the one or more openings is configured to receive an intermediate leg of the engagement structure.

EXAMPLE 74

The ceiling fan blade of example 73, wherein the engagement structure includes one or more intermediate legs configured to be received in the one or more openings when the fan blade is in the socket and the engagement structure is in its first position.

EXAMPLE 75

The ceiling fan blade of any of examples 1-57 or 66, wherein the first end of the fan blade comprises an annular portion.

EXAMPLE 76

The ceiling fan blade of any of examples 1-57 or 66-75 that includes a biasing member to bias the engagement structure to the first portion, and the engagement structure can be moved to the second position by an ahl or similar tool pushed through an opening in the socket and against the engagement structure.

EXAMPLE 77

The ceiling fan blade of any of examples 1-56 or 65-74 that includes a biasing member to bias the engagement structure to the first portion, and the engagement structure can be moved to the second position by an ahl or similar tool pushed through an opening in the socket and against the engagement structure can be moved to the second position by pulling a handle attached to the biasing member or the engagement structure.

EXAMPLE 78

The ceiling fan blade of any of examples 19-20, wherein there is a spring on the pivot rod.

EXAMPLE 79

The ceiling fan blade of any of examples 1-20 or 78, wherein the fan blade has a body and one or more openings in the body and the engagement structure further includes one or more central legs between the first leg and the second leg, wherein each of the one or more central legs is configured to be received in one of the one or more openings when the engagement structure is in its first position.

EXAMPLE 80

The ceiling fan blade of example 79, wherein there is one central leg configured to be received in one opening in the body of the fan blade.

EXAMPLE 81

The ceiling fan blade of any of examples 1-20 or 78-80, wherein a biasing member is attached to the engagement structure.

EXAMPLE 82

The ceiling fan blade of any of examples 1-14, 16-20, or 78-80, wherein biasing member biases the engagement member to its first position.

EXAMPLE 83

The ceiling fan blade of example 81 in which the biasing member can be moved to a retracted position that moves the engagement member to its second position.

EXAMPLE 84

The ceiling fan blade of example 28 or 38, wherein the engagement structure comprises one or more legs and the fan blade comprises a first side and a second side and a recess on one or both of the first side and second side, wherein one of the one or more legs engage each recess when the engagement structure is in its first position.

EXAMPLE 85

The ceiling fan blade of example 84, wherein the fan blade has a recess on the first side and the engagement structure has a first leg to be configured to engage the recess when the engagement structure is in its first position.

EXAMPLE 86

The ceiling fan blade of example 84, wherein the fan blade has a recess on the first side and a recess on the second side and a first leg configured to engage the first recess when the engagement structure is in its first position and a second leg configured to engage the second recess when the engagement structure is in its first position.

EXAMPLE 87

The ceiling fan blade of any of examples 28, 38 or 84-86, wherein the fan blade has a body and one or more openings in the body, and the engagement structure has one or more central legs, wherein at least one of the one or more central legs is configured to be received in one of the one or more openings when the engagement structure is in its first position.

EXAMPLE 88

The ceiling fan blade of example 87, wherein the fan blade body has one opening and the engagement structure has one central leg configured to be received in the opening when the engagement structure is in its first position.

EXAMPLE 89

The ceiling fan blade of example 87, wherein the fan blade body has a plurality of openings and the engagement structure has a plurality of central legs, and each of the plurality of central protrusions is configured to be received in one of the plurality of openings when the engagement structure is in its first position.

EXAMPLE 90

The ceiling fan blade of any of examples 28, 38, or 84-89, wherein the engagement structure has an inner surface comprising a surface feature and the surface feature is pressed against a surface of the fan blade when the engagement structure is in its first position.

EXAMPLE 91

The ceiling fan blade of any of examples 28, 38, or 84-90, wherein the engagement structure moves straight up and down between its first position and second position.

EXAMPLE 92

The ceiling fan blade of any of examples 28, 38, or 84-90, wherein the engagement structure moves up and down at an angle between its first position and second position.

EXAMPLE 93

The ceiling fan blade of any of examples 28, 38, or 84-90, wherein the engagement structure is attached to pivot rod and moves up and down among a curve between its first position and second position.

EXAMPLE 94

The ceiling fan blade of any of examples 28, 38 or 84-91 that includes an engagement structure comprising independent, spaced-apart legs.

EXAMPLE 95

The ceiling fan blade of example 94, wherein there is a separate biasing member for each independent leg and each biasing member biases the independent leg with which it is associated to the first position.

EXAMPLE 96

The ceiling fan blade of any of examples 28, 38, or 84-91 that includes an engagement structure that comprises a single leg.

EXAMPLE 97

The ceiling fan blade of example 96 that includes a biasing member that biases the single leg towards its first position.

Having thus described different embodiments, other variations and embodiments that do not depart from the spirit of this disclosure will become apparent to those skilled in the art. The scope of the claims is thus not limited to any particular embodiment, but is instead set forth in the claims and the legal equivalents thereof. Unless expressly stated in the written description or claims, the steps of any method recited in the claims may be performed in any order capable of yielding the desired product. No language in the specification should be construed as indicating that any non-claimed limitation is included in a claim. The terms “a” and “an” in the context of the following claims are to be construed to cover both the singular and the plural, unless otherwise indicated herein. 

What is claimed is:
 1. A ceiling fan having a hub with a plurality of sockets, wherein each socket has an open end and is configured to receive a first end of a fan blade, wherein the ceiling fan further comprises: (a) an engagement structure positioned at least partially in each socket, the engagement structure having a first position in which it does not engage the first end of the fan blade and a second position in which the engagement structure engages the first end of the fan blade; and (b) the first end of the fan blade has a first side and a second side, wherein the first side has a first recess and the second side has a second recess and the engagement structure has a first leg that engages the first recess when the engagement structure is in its first position, and a second leg that engages the second recess when the engagement structure is in its first position.
 2. The ceiling fan of claim 1, wherein the first end of the fan further comprises one or more surface features.
 3. The ceiling fan of claim 2, wherein the engagement structure further comprises one or more surface features that engage the one or more surface features on the first end of the fan blade when the engagement structure is in its first position.
 4. The ceiling fan of claim 1, wherein the first end of the fan blade further comprises a tacky surface.
 5. The ceiling fan of claim 1, wherein the engagement structure further comprises a tacky surface that is configured to be pressed against the first end of the fan blade when the engagement structure is in its first position.
 6. The ceiling fan of claim 4, wherein the engagement structure comprises a tacky surface that is configured to be pressed against the first end of the fan blade when the engagement structure is in its first position.
 7. The ceiling fan of claim 1, wherein the fan blade has a top surface and a bottom surface and a tacky coating on one or both of the top surface and the bottom surface.
 8. The ceiling fan of claim 1, wherein the engagement structure has a front portion with height H1 and the first leg and the second leg each have a height H2, wherein H2 is greater than H1.
 9. The ceiling fan of claim 6, wherein the socket has an interior height and the first end of the fan has a thickness that is less than the combined interior height of the socket and H1.
 10. The ceiling fan of claim 1, wherein the first leg and second leg each have a side that is curved or angled.
 11. The ceiling fan of claim 1 that includes a plurality of sockets and a plurality of fan blades, wherein one of the plurality of fan blades is received in one of the plurality of sockets.
 12. The ceiling fan of claim 10 that comprises four sockets one fan blade in each socket.
 13. The ceiling fan of claim 1, wherein the engagement structure is biased to the first position.
 14. The ceiling fan of claim 12, wherein the engagement structure is biased to the first position by a spring.
 15. The ceiling fan of claim 1, wherein each leg has a proximal side configured to engage the end of the fan blade and move the engagement structure into the second position in response to pressure from the first end of the fan.
 16. The ceiling fan of claim 1, wherein the engagement structure is moved between its first position and its second position by a manual switch.
 17. The ceiling fan of claim 16, wherein the switch is directly or indirectly connected to the engagement structure.
 18. The ceiling fan of claim 1 that further incudes a pivot rod around which the engagement structure pivots.
 19. The ceiling fan of claim 16 that further incudes a pivot rod in the hub around which the engagement structure and the manual switch pivot.
 20. The ceiling fan of claim 1 that further includes a first biasing member for biasing the first leg to the first position and a second biasing member for biasing the second leg to the first position. 